This invention relates generally to a device for dispensing units of platform-loaded goods from a stack of one or more units of platform-loaded goods onto a receptacle such as a rack.
Many products on the market are sold loaded upon regularly-sized platforms. For example, pipette tips used for sample testing in laboratories are typically loaded into pipette tip flats so that the user need not handle the pipette tips individually. By utilizing platform loading, goods can be efficiently stored and transported in large quantities, as the platforms can be stacked and/or packaged one atop the other.
In many applications it is desirable to utilize a device which facilitates dispensing of platforms from a stack. For example, hand loading of pipette tip flats onto pipette tip racks is generally difficult and inefficient, as the pipette tip flat must be steadily maintained in parallel and aligned with the pipette tip rack for the pipette tips extending through the flat to register with and fit into the rack. Further, in applications where contamination of the goods loaded onto the platforms is a concern or where the goods are dangerous if handled by human operators, utilizing a device for unloading the platforms removes the risks of contamination and/or injury posed by human handling of the platforms.
A single laboratory or other facility utilizing such a dispensing aid will frequently use the same platforms to store goods of varying sizes and shapes. Accordingly, while dispensing devices are typically constructed to accommodate platforms of a predetermined size and shape, the dispensing device optimally will dispense those platforms when loaded with any size or shape of goods that allow the platforms to be stacked. Further, depending on the application desired, the user may wish to unload more than one platform from the dispensing aid at one time.
A number of devices have been developed that facilitate unloading pipette tip flats from a stack of pipette tip flats. U.S. Pat. Nos. 5,392,914 and 5,441,702 to Lemieux et al., and U.S. Pat. No. 5,779,984 to Kelly et al. each describe refill packs for pipette tip racks. The refill packs described in those patents enclose stacks of pipette tip flats in a box-like package having an open lower end from which the pipette tips in the lowest flat in the stack extend. The package is grasped by the user and the pipette tips in the lowermost flat are manually fitted into a pipette tip rack. The pipette tip flats are held within the rack by a flange extending around the perimeter of the open end of the refill pack. When the package is pressed downwardly, the flange is deformed outwardly by the downward force exerted by the lowermost pipette tip flat, and the flat is forced through the flange and remains on the rack. Once the flat has passed through the flange, the flange elastically returns to its original position, retaining the rest of the pipette tip flats within the package.
U.S. Pat. No. 5,470,538 to Lind describes a pipette tip rack loader (xe2x80x9cthe ""538 loaderxe2x80x9d) wherein a stack of pipette tip flats is loaded onto an upper platform which is spring biased to an elevated position and delivered to a pipette tip rack positioned on a stationary base below the upper platform. When the upper platform is depressed toward the pipette tip rack, slides supporting the stack of pipette tips retract, allowing the stack of pipette tips to fall onto the rack through the platform. As the upper platform is retracted to its upper position by the spring bias, the slides move inwardly to engage underneath the second pipette tip flat in the stack, leaving a single pipette tip flat on the rack.
U.S. Pat. No. 5,948,362 to Steinbrenner describes an apparatus for unloading stacked pipette tip flats (xe2x80x9cthe ""362 apparatusxe2x80x9d). The ""362 apparatus includes a magazine which holds the pipette tip flats and utilizes an retaining element at its lower end which holds the pipette tip flats within the magazine except when the retaining element is activated to release the flats. The pipette tip flats are delivered onto a support such as an autoclave box with upraised flanges on either side. When the magazine is pressed down onto the autoclave box or the autoclave box is pressed upwardly against the magazine, the upraised flanges or edges of the autoclave box force the retaining element to move outwardly. In the various embodiments of the device, the height of the flanges, the positioning of vertical stops within the magazine limiting the insertion of the autoclave box, or the type of retaining element used is preselected such that for pipette tips of a desired size, only a single pipette tip flat will be dispensed when the retaining element is forced outwardly.
While the above-mentioned devices offer various advantages over the manual handling of pipette tip flats, there exists a continuing need for a reusable dispensing device which can dispense units of platform loaded goods of various sizes and shapes, can dispense one or more units of platform-loaded goods in a single dispensing action, and can be simply and reliably operated by an automated system processing the units of platform loaded goods.
Accordingly, it is an object of the present invention to provide a dispensing device which will dispense units of platform loaded goods of varying heights.
Another object of the present invention is to provide a dispensing device which will allow a user to deliver one or more units of platform loaded goods from a dispenser onto a receptacle in a single dispensing action.
A further object of the present invention is to provide a dispensing device which aligns platforms dispensed by the device with the receptacle to which they are delivered.
Other objects and advantages of the current invention will become apparent when the inventive platform loader is considered in conjunction with the accompanying drawings, specification, and claims.
A device for dispensing units of platform-loaded goods from a stack of one or more units of platform-loaded goods is provided which comprises a dispenser including a dispenser frame, capture blades, and blade control means. The dispenser frame forms a central aperture which defines a plane. The aperture has sufficiently large dimensions to allow passage of a units of platform-loaded goods therethrough when the unit is maintained in parallel with the plane. The capture blades retain the stack within the dispenser when they are in a closed position, and release the stack when they are in an open position such that units of platform-loaded goods in the stack can pass through the aperture. The blade control means opens and closes the capture blades, and is biased to hold the capture blades in the closed position.
The device also includes means for engaging the dispenser such that the blade control means are moved upwardly in relation to the dispenser frame to open the capture blades, allowing one or more units of platform loaded goods in the stack to fall through the aperture.
A dispenser platform for dispensing units of platform-loaded goods is further provided which comprises a plurality of dispensers forming a dispenser assembly, and means for rotating the dispenser assembly. Each dispenser includes a dispenser frame forming a central aperture, capture blades for retaining a stack of units of platform-loaded goods within the dispenser when the capture blades are in a closed position and for releasing the stack when in an open position such that one or more units of platform-loaded goods in the stack can pass through the aperture, and blade control means for opening and closing the capture blades. The blade control means are biased to hold the capture blades in the closed position. The plurality of dispensers are positioned within the dispenser assembly such that at least one region of the dispenser assembly is defined wherein when the dispenser assembly is rotated each dispenser in the assembly may successively be positioned within the region and activated to release one or more units of platform-loaded goods.
An automated dispensing system for dispensing units of platform loaded goods is also provided, which comprises at least one dispenser, engaging means for engaging each dispenser, means for moving the engaging means, lifting means for moving the engaging means vertically, and a control system for operating the rotation means and lifting means. Each dispenser used in the automated dispensing system includes a dispenser frame forming a central aperture, capture blades for retaining a stack of the units of platform-loaded goods within the dispenser when in a closed position and for releasing the stack when in an open position such that one or more units of platform-loaded goods in the stack can pass through the aperture, and blade control means for opening and closing the capture blades which are biased to hold the capture blades in the closed position.
The engaging means are capable of engaging each dispenser such that its blade control means are moved upwardly in relation to its dispenser frame to open its capture blades, allowing one or more units of platform-loaded goods in its stack to fall through its aperture. The means for moving the engaging means moves the engaging means over a first range, such that within the first range the engaging means can be positioned with respect to at least one dispenser such that if it is raised it will engage the dispenser, and such that the engaging means also can be positioned at a delivery site. The lifting means are operable to move the engaging means vertically over a second range, such that within the second range the engaging means can be moved into and out of engagement with the at least one dispenser.